Extruded cellular ceramic articles are used as particulate filters and catalytic converters in internal combustion engines. The extruded cellular ceramic article includes a web array made up of thin web walls (“webs”). The web array defines an array of densely packed cells (e.g., 15 to 200 cells per square centimeter). An outer skin may define the shape of the article and may support the internal web array. The web array provides a relatively large surface area for catalytic material to react with the exhaust gases that pass through the cells.
The mechanical or thermal integrity of an extruded cellular ceramic article can be substantially compromised by defects in the web array or skin. The web array defects may manifest in a variety of different forms, e.g., distorted cells, collapsed cells, sheared cells, missing web arrays, etc. The skin defects may present as deviations in the overall ideal contour shape, localized variations such as indentations or protrusions, or fissures.